16 S. S. COHEN 



1. Mitchondria 81 



E. Enzymatic Systems in the Microsomal Fraction 86 



F. Enzymatic Activities of Cell Sap 87 



G. Polymer Synthesis in Cytoplasm and Nucleus 88 



1. Methodology 88 



2. Protein Synthesis 88 



3. RNA Synthesis 99 



IV. Patterns of Polymer Synthesis 103 



A. Exponential Growth 103 



B. Differentiated Cells 104 



C. Synchronous Cultures 107 



D. Pathological Systems 109 



E. Unbalanced Growth HI 



1 . Thymineless Death Ill 



2. Mode of Action of Penicillin 114 



3. Diaminopitnelic Acid Deficiency 116 



4. Carotenoid Deficiencies in Photosynthetic Bacteria 116 



F. Syntheses with Abnormal Metabolites 118 



G. Problems of Turnover ] 20 



1, Proteins 120 



2. Nucleic Acids 123 



V. Controlling Mechanisms of Enzyme and Protein Synthesis 128 



A. Introduction 128 



B. Genetic Controls 129 



C. Some Nutritional Phenomena 135 



D. The Induced Biosynthesis of Enzymes 1 37 



1. General Remarks 137 



2. Problems of Protein SjTithesis in Inducible Systems 140 



3. Role of Nucleic Acids in Inducible Systems 142 



4. On Induction 144 



5. On Cell Permeability and Enzyme Synthesis 146 



6. On the Inhibition of Enzyme Formation 1 48 



7. Inducible Phenomena in Higher Forms 150 



VI. Biochemical Mechanisms of Poljoner Formation 151 



A. Phosphate Transfer 153 



1. Hydrolases and Transferases 154 



2. Kinases 155 



3. Pyrophosphorylases 157 



4. Phosphorylases 1 61 



5. On Phosphoproteins 1 63 



B. Polysaccharide Biosynthesis 1 63 



1. Phosphorylases and Other Enzymes 1 63 



2. Transglycosidases and Hydrolases 1 65 



3. Systems Utilizing Nucleoside Diphosphosugars 166 



C. Phospholipid Sjmthesis 1 67 



D. Mechanisms of Peptide Synthesis 168 



1. Transpeptidation 169 



2. Carboxyl Activation in Model Systems 171 



3. Carboxyl Activation of Amino Acids 1 73 



4. Intermediate Reactions 174 



